2006-11-25 11:49:17 -07:00
|
|
|
Name
|
|
|
|
|
|
|
|
|
|
MESA_ycbcr_texture
|
|
|
|
|
|
|
|
|
|
Name Strings
|
|
|
|
|
|
|
|
|
|
GL_MESA_ycbcr_texture
|
|
|
|
|
|
|
|
|
|
Contact
|
|
|
|
|
|
|
|
|
|
Brian Paul, Tungsten Graphics, Inc. (brian.paul 'at' tungstengraphics.com)
|
|
|
|
|
Keith Whitwell, Tungsten Graphics, Inc. (keith 'at' tungstengraphics.com)
|
|
|
|
|
|
|
|
|
|
Status
|
|
|
|
|
|
|
|
|
|
Shipping (Mesa 4.0.4 and later)
|
|
|
|
|
|
|
|
|
|
Version
|
|
|
|
|
|
|
|
|
|
1.0
|
|
|
|
|
|
|
|
|
|
Number
|
|
|
|
|
|
|
|
|
|
TBD
|
|
|
|
|
|
|
|
|
|
Dependencies
|
|
|
|
|
|
|
|
|
|
OpenGL 1.0 or later is required
|
2012-08-17 07:57:59 -06:00
|
|
|
This extension is written against the OpenGL 1.4 Specification.
|
2006-11-25 11:49:17 -07:00
|
|
|
NV_texture_rectangle effects the definition of this extension.
|
|
|
|
|
|
|
|
|
|
Overview
|
|
|
|
|
|
|
|
|
|
This extension supports texture images stored in the YCbCr format.
|
|
|
|
|
There is no support for converting YCbCr images to RGB or vice versa
|
|
|
|
|
during pixel transfer. The texture's YCbCr colors are converted to
|
|
|
|
|
RGB during texture sampling, after-which, all the usual per-fragment
|
|
|
|
|
operations take place. Only 2D texture images are supported (not
|
|
|
|
|
glDrawPixels, glReadPixels, etc).
|
|
|
|
|
|
|
|
|
|
A YCbCr pixel (texel) is a 16-bit unsigned short with two components.
|
|
|
|
|
The first component is luminance (Y). For pixels in even-numbered
|
|
|
|
|
image columns, the second component is Cb. For pixels in odd-numbered
|
|
|
|
|
image columns, the second component is Cr. If one were to convert the
|
|
|
|
|
data to RGB one would need to examine two pixels from columns N and N+1
|
|
|
|
|
(where N is even) to deduce the RGB color.
|
|
|
|
|
|
|
|
|
|
IP Status
|
|
|
|
|
|
|
|
|
|
None
|
|
|
|
|
|
|
|
|
|
Issues
|
|
|
|
|
|
|
|
|
|
None
|
|
|
|
|
|
|
|
|
|
New Procedures and Functions
|
|
|
|
|
|
|
|
|
|
None
|
|
|
|
|
|
|
|
|
|
New Tokens
|
|
|
|
|
|
|
|
|
|
Accepted by the <internalFormat> and <format> parameters of
|
|
|
|
|
TexImage2D and TexSubImage2D:
|
|
|
|
|
|
|
|
|
|
YCBCR_MESA 0x8757
|
|
|
|
|
|
|
|
|
|
Accepted by the <type> parameter of TexImage2D and TexSubImage2D:
|
|
|
|
|
|
|
|
|
|
UNSIGNED_SHORT_8_8_MESA 0x85BA /* same as Apple's */
|
|
|
|
|
UNSIGNED_SHORT_8_8_REV_MESA 0x85BB /* same as Apple's */
|
|
|
|
|
|
|
|
|
|
Additions to Chapter 2 of the OpenGL 1.4 Specification (OpenGL Operation)
|
|
|
|
|
|
|
|
|
|
None
|
|
|
|
|
|
|
|
|
|
Additions to Chapter 3 of the OpenGL 1.4 Specification (Rasterization)
|
|
|
|
|
|
|
|
|
|
In section 3.6.4, Rasterization of Pixel Rectangles, on page 101,
|
|
|
|
|
add the following to Table 3.8 (Packed pixel formats):
|
|
|
|
|
|
|
|
|
|
type Parameter GL Data Number of Matching
|
|
|
|
|
Token Name Type Components Pixel Formats
|
|
|
|
|
-------------- ------- ---------- -------------
|
|
|
|
|
UNSIGNED_SHORT_8_8_MESA ushort 2 YCBCR_MESA
|
|
|
|
|
UNSIGNED_SHORT_8_8_REV_MESA ushort 2 YCBCR_MESA
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
In section 3.6.4, Rasterization of Pixel Rectangles, on page 102,
|
|
|
|
|
add the following to Table 3.10 (UNSIGNED_SHORT formats):
|
|
|
|
|
|
|
|
|
|
UNSIGNED_SHORT_8_8_MESA:
|
|
|
|
|
|
|
|
|
|
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
|
|
|
|
|
+-------------------------------+-------------------------------+
|
|
|
|
|
| 1st | 2nd |
|
|
|
|
|
+-------------------------------+-------------------------------+
|
|
|
|
|
|
|
|
|
|
UNSIGNED_SHORT_8_8_REV_MESA:
|
|
|
|
|
|
|
|
|
|
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
|
|
|
|
|
+-------------------------------+-------------------------------+
|
|
|
|
|
| 2nd | 1st |
|
|
|
|
|
+-------------------------------+-------------------------------+
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
In section 3.6.4, Rasterization of Pixel Rectangles, on page 104,
|
2012-08-17 07:57:59 -06:00
|
|
|
add the following to Table 3.12 (Packed pixel field assignments):
|
2006-11-25 11:49:17 -07:00
|
|
|
|
|
|
|
|
First Second Third Fourth
|
|
|
|
|
Format Element Element Element Element
|
|
|
|
|
------ ------- ------- ------- -------
|
|
|
|
|
YCBCR_MESA luminance chroma
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
In section 3.8.1, Texture Image Specification, on page 125, add
|
|
|
|
|
another item to the list of TexImage2D and TexImage3D equivalence
|
|
|
|
|
exceptions:
|
|
|
|
|
|
|
|
|
|
* The value of internalformat and format may be YCBCR_MESA to
|
|
|
|
|
indicate that the image data is in YCbCr format. type must
|
|
|
|
|
be either UNSIGNED_SHORT_8_8_MESA or UNSIGNED_SHORT_8_8_REV_MESA
|
|
|
|
|
as seen in tables 3.8 and 3.10. Table 3.12 describes the mapping
|
|
|
|
|
between Y and Cb/Cr to the components.
|
|
|
|
|
If NV_texture_rectangle is supported target may also be
|
|
|
|
|
TEXTURE_RECTANGLE_NV or PROXY_TEXTURE_RECTANGLE_NV.
|
|
|
|
|
All pixel transfer operations are bypassed. The texture is stored as
|
|
|
|
|
YCbCr, not RGB. Queries of the texture's red, green and blue component
|
|
|
|
|
sizes will return zero. The YCbCr colors are converted to RGB during
|
|
|
|
|
texture sampling using an implementation dependent conversion.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
In section 3.8.1, Texture Image Specification, on page 126, add
|
|
|
|
|
another item to the list of TexImage1D and TexImage2D equivalence
|
|
|
|
|
exceptions:
|
|
|
|
|
|
|
|
|
|
* The value of internalformat and format can not be YCBCR_MESA.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
In section 3.8.2, Alternate Texture Image Specification Commands, on
|
|
|
|
|
page 129, insert this paragraph after the first full paragraph on the
|
|
|
|
|
page:
|
|
|
|
|
|
|
|
|
|
"If the internal storage format of the image being updated by
|
|
|
|
|
TexSubImage2D is YCBCR_MESA then format must be YCBCR_MESA.
|
|
|
|
|
The error INVALID_OPERATION will be generated otherwise."
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Additions to Chapter 4 of the OpenGL 1.4 Specification (Per-Fragment
|
|
|
|
|
Operations and the Frame Buffer)
|
|
|
|
|
|
|
|
|
|
None
|
|
|
|
|
|
|
|
|
|
Additions to Chapter 5 of the OpenGL 1.4 Specification (Special Functions)
|
|
|
|
|
|
|
|
|
|
None
|
|
|
|
|
|
|
|
|
|
Additions to Chapter 6 of the OpenGL 1.4 Specification (State and
|
|
|
|
|
State Requests)
|
|
|
|
|
|
|
|
|
|
None
|
|
|
|
|
|
|
|
|
|
Additions to Appendix A of the OpenGL 1.4 Specification (Invariance)
|
|
|
|
|
|
|
|
|
|
None
|
|
|
|
|
|
|
|
|
|
Additions to the AGL/GLX/WGL Specifications
|
|
|
|
|
|
|
|
|
|
None
|
|
|
|
|
|
|
|
|
|
GLX Protocol
|
|
|
|
|
|
|
|
|
|
None
|
|
|
|
|
|
|
|
|
|
Errors
|
|
|
|
|
|
|
|
|
|
INVALID_ENUM is generated by TexImage2D if <internalFormat> is
|
|
|
|
|
MESA_YCBCR but <format> is not MESA_YCBCR.
|
|
|
|
|
|
|
|
|
|
INVALID_ENUM is generated by TexImage2D if <format> is MESA_YCBCR but
|
|
|
|
|
<internalFormat> is not MESA_YCBCR.
|
|
|
|
|
|
|
|
|
|
INVALID_VALUE is generated by TexImage2D if <format> is MESA_YCBCR and
|
|
|
|
|
<internalFormat> is MESA_YCBCR and <border> is not zero.
|
|
|
|
|
|
|
|
|
|
INVALID_OPERATION is generated by TexSubImage2D if the internal image
|
|
|
|
|
format is YCBCR_MESA and <format> is not YCBCR_MESA.
|
|
|
|
|
|
|
|
|
|
INVALID_OPERATION is generated by CopyTexSubImage2D if the internal
|
|
|
|
|
image is YCBCR_MESA.
|
|
|
|
|
|
|
|
|
|
New State
|
|
|
|
|
|
|
|
|
|
Edit table 6.16 on page 231: change the type of TEXTURE_INTERNAL_FORMAT
|
|
|
|
|
from n x Z42 to n x Z43 to indicate that internal format may also be
|
|
|
|
|
YCBCR_MESA.
|
|
|
|
|
|
|
|
|
|
Revision History
|
|
|
|
|
|
|
|
|
|
20 September 2002 - Initial draft
|
|
|
|
|
29 April 2003 - minor updates
|
|
|
|
|
3 September 2003 - further clarify when YCbCr->RGB conversion takes place
|
|
|
|
|
19 September 2003 - a few more updates prior to submitting to extension
|
|
|
|
|
registry.
|
|
|
|
|
3 April 2004 - fix assorted inaccuracies
|
